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  <font color="red" size="7">字体标签</font>
  <em>强调斜体</em>
  <i>斜体</i>
  <b>加粗</b>
  <strong>强调加粗</strong>
  <u>下划线</u>
  &lt;h1>教学h1&lt;/h1>
  &lt;h1&gt;教学h1&lt;/h1&gt;
  <hr>
  密&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;码
  <pre>
    密      码
    用  户  名
  </pre>
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